TransCore encompass 4, Руководство пользователя

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To set the frequency range
1. Ensure that the host computer is in command mode.
2. Enter command
#647XXX
–
where XXX is a hexadecimal value from 000 to 118
–
and press ENTER .
See command “647NNN Select RF Operating Frequency” on page 7–121 for a complete listing of
the hexadecimal values and the corresponding frequencies. For backward compatible frequency
selection, see command “642NN Select RF Operating Frequency” on page 7–118 .
3. To verify that the RF has been changed to the proper setting, type in command #527 to see the
current frequency setting.
Caution
Contact TransCore if your application requires a frequency outside of the authorized frequency
range.
RF Transmission
The RF transmission can be controlled by one of the following methods:
• Connecting a vehicle detector to the sense input0 circuit
• The host sending software commands to the Encompass 4 Reader
As a factory default, the Encompass 4 Reader is configured to control the RF power with a vehicle
detector.
Figure 51 illustrates the methods of controlling RF sense output.
Vehicle Detector Controlling RF Transmission
The vehicle detector can be a loop detector, an infrared sensor, or an ultrasonic detector which can be
connected to the sense input0 to turn on the Encompass 4 Reader RF. Figure 51 shows a vehicle detector
controlling the RF. This operation is preferred because the RF transmits only when a vehicle is in the read
zone. Command
#641
Select RF-by-Input Control (factory default) must be enabled.
Host Controlling RF Transmission
Alternately, RF output can be controlled by commands sent to the reader.
Commands
#6400 RF Off
and
#6401 RF On
turn RF on and off.
Figure 51 RF ON by Sense Input (641 Factory Default)
Encompass 4 Reader System Guide
TransCore Proprietary.
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